fix broken link (#2059)

(cherry picked from commit 7d26a87)

docs/ibc/relayer.md

@@ -27,7 +27,7 @@ a module event emission with the attribute value `ibc_<submodulename>` (02-clien
 
 ### Subscribing with Tendermint 
 
-Calling the Tendermint RPC method `Subscribe` via [Tendermint's Websocket](https://docs.tendermint.com/v0.35/rpc/) will return events using
+Calling the Tendermint RPC method `Subscribe` via [Tendermint's Websocket](https://docs.tendermint.com/main/rpc/) will return events using
 Tendermint's internal representation of them. Instead of receiving back a list of events as they
 were emitted, Tendermint will return the type `map[string][]string` which maps a string in the
 form `<event_type>.<attribute_key>` to `attribute_value`. This causes extraction of the event